A general configuration is known for articulated arms for awnings that has become classic and according to which, the arm comprises an arm and forearm consisting of first and second tubular elements with parts at their ends connected to a plug defined by articulation configurations. The arm and forearm are connected together by an articulation consisting of two of the said adjacent articulation configurations. The articulation configuration joined to the arm includes a fork consisting of a pair of facing lugs containing coaxial holes, whereas the articulation configuration joined to the forearm defines a core with an axial hole aligned with the cited coaxial holes of the lugs for the insertion of an articulation pin. Within the first profile, which forms the arm body, there is a traction spring joined at one end to a fixed point on the first tubular profile and, by a second end to a flexible pulling element, which is, in turn, fixed to a point on the said core in the forearm articulation configuration and the said flexible pulling elements is supported on a surface of the core that is located away from the articulation's rotation shaft in order to create, in virtue of the tension exerted by the traction spring, a torque that will tend to maintain the arm and forearm in an open position.
In conventional designs, the cited flexible pulling element consists of one or more transmission chains, or one or more thick twisted cables, a portion of which is inevitable exposed and visible within the articulation zone. This exposure of the chain or cable involves the risk of dirt accumulating in the articulation zone and moreover, produces an anti-aesthetic effect in a product that is destined to be permanently in view of the public.
The application for international patent WO 98/01638 belonging to the current applicant makes known an articulated arm for the support of awnings that includes a series of improvements in the articulation configuration and where the mentioned flexible pulling element consists of a flat belt interiorly fitted with metal reinforcement filaments. This belt includes terminals at its two ends for joining the belt to the traction spring and the core respectively. The said terminals are shaped using casting technology and are joined to the said metal filaments, which project from the ends of the belt, during the casting process. In addition to greatly facilitating the assembly of the awning arm, this flat belt permits a more compact articulation design and can be made from plastic in the same colour as the rest of the arm so that it provides a sufficiently aesthetic appearance and can remain partially in view without any additional trim pieces being required.
Utility model ES-A-1052733 describes a model for an awning arm of this type in which the pulling element consists of a pair of thick twisted cables and where a curved top is employed to cover the sides of these twisted cables in an articulation zone. One inconvenience of such a design is that the thick cables produce an excessively wide articulation and the mentioned top is another part which adds to the complexity to the articulation and increases its cost.
One objective of this invention is that of providing an awning articulated arm in which the articulation between arm and forearm forms a compact, closed assembly, where the flexible pulling element is completely hidden from sight and protected by the articulation's own configurations.